J. Mangano, MPH, MBA
November 12, 2007
TABLE OF CONTENTS
from Indian Point
of Improved Health After Reactor Shutdown
The Indian Point nuclear plant, 35 miles north of midtown Manhattan, has three reactors, two of which remain in operation. Entergy Nuclear, which operates the plant, has requested that the federal government extend the operating licenses of the two reactors for 20 additional years beyond their 2013 and 2015 expiration dates.
To date, federal officials have not acknowledged any public health risks of license extension at Indian Point. This report explores risks from extending the Indian Point licenses.
Continued operation of Indian Point raises the risk of radioactivity exposure in two ways.
The principal findings of this report are:
The discovery of nuclear fission, or creation of high energy by splitting uranium atoms, was first used for military purposes, i.e. the atomic bombs in Japan during World War II. Soon after, other uses of the fission process were introduced. One of these was the creation of electric power from the heat generated by fission. The “Atoms for Peace” speech given at the United Nations by President Dwight Eisenhower in 1953 opened the door for the development of reactors that would produce electricity.
Hundreds of reactors were proposed by electric utilities, who were interested based on the potential to produce clean and cheap energy. In the New York City area, many reactors were discussed, and federal applications were formally submitted for a total of 16 within 100 miles of midtown Manhattan (Table 1). Of these, only five eventually operated and only three still remain in operation (Indian Point 2, Indian Point 3, and Oyster Creek).
The Indian Point plant is the former site of an amusement park in the town of Buchanan, in northwestern Westchester County. It is located on the Hudson River, the source of power needed to operate the plant. Five reactors were once proposed for the site; however, the Verplanck 1 and 2 reactors were cancelled in the 1970s, and the Indian Point unit 1 reactor closed permanently in 1974.
The Indian Point units 2 and 3 reactors
have the capacity to generate 951 and 965 megawatts of electricity, respectively,
much more than the unit 1 capacity of 257. The reactors went critical
(began producing radioactivity) on May 22, 1973 and April 6, 1976, respectively.
To date, no U.S. reactor has operated longer than 38 years, making the
34 and 31 year-old Indian Point reactors among the oldest.
B. Radioactivity Produced in Reactors
To produce electricity, nuclear power reactors split uranium-235 atoms, generating high energy that is transformed into electrical power. This splitting process, known as fission, also produces over 100 chemicals not found in nature. These chemicals are the same as those found in the large clouds of fallout after above-ground atomic bomb tests.
Fission products, which take the form of gases and particles, include Cesium-137, Iodine-131, and Strontium-90. They are highly unstable atoms which emit alpha particles, beta particles, or gamma rays. When they enter the body, they affect various organs. Cesium seeks out the muscles (including the heart and reproductive organs), iodine attacks the thyroid gland, and strontium attaches to bone. Each causes cancer after damaging DNA in cells and creating mutations, and is especially harmful to the fetus, infant, and child. Some decay quickly (Iodine-131 has a half life of 8 days), while others remain for long periods (Strontium-90 has a half life of 29 years).
Most of the radioactivity produced in reactors is contained within the reactor building and stored as high-level waste in deep pools of water that must be constantly cooled. At Indian Point and at other aging plants, the pools are becoming full. Some of the waste has been transferred to above-ground outdoor casks, and this process is expected to begin at Indian Point in late 2007. Indian Point currently maintains over 1,500 tons of waste on site, and additional radioactivity in the reactor cores. The amount of radioactivity at the plant is equivalent to several times as much as present at the Chernobyl site, and hundreds of times as much as was released at Hiroshima in 1945.
The federal government has designated Yucca
Mountain in Nevada as a permanent waste site. Yucca has encountered much
opposition, and will not open until at least 2018 (according to the U.S.
Energy Department). Some experts believe that Yucca Mountain or any permanent
repository will never open, leaving existing nuclear plants to maintain
the waste indefinitely.
II. Health Hazards Posed by Reactor
Much of the health concern posed by nuclear reactors is on the effects of a major meltdown. The radioactivity in a reactor core and waste pools must be constantly cooled by water, or the fuel will heat uncontrollably, causing a huge release of radioactivity. This release can be caused by mechanical failure (such as what happened at Chernobyl in 1986, when safeguard redundancy was deliberately shut off for testing purposes) or by a deliberate act of sabotage.
The experience at Hiroshima and Nagasaki
demonstrated how exposure to high levels of radioactivity can harm humans.
Those closest to the bombs were vaporized, literally melting from the
intense heat. But many other victims who survived the initial blast developed
acute radiation poisoning, marked by symptoms such as nausea, vomiting,
diarrhea, skin burns, weakness, dehydration, bleeding, hair loss, ulcerations,
bloody stool, and skin sloughing (falling off), according to the Medical
Encyclopedia of the National Library of Medicine. In addition, a large
number of bomb survivors in the two cities developed cancers over the
next several decades; thyroid cancer had the greatest excess, according
to a 1994 report. (Source: Thompson DE et al. Cancer Incidence in Atomic
Bomb Survivors. Part II: Solid Tumore, 1958-1987. Radiation Effects Research
Foundation, Hiroshima Japan, 1994).
B. Estimates of Casualties
If a meltdown that caused large scale releases of radioactivity from the reactor core or the waste pools occurred at Indian Point, there would be no vaporizing of humans. However, many would suffer from acute radiation poisoning (in the short term) and cancer (in the long term). Several estimates have been made to calculate just how many would be harmed. In 1982, the Sandia National Laboratories submitted estimates to Congress for each U.S. nuclear plant in the case of core meltdown. Those estimates for Indian Point are given in Table 2.
The Sandia figures are known as CRAC-2 (for Calculation of Reactor Accident Consequences). CRAC-2 estimated casualties for Indian Point are one of the highest of any U.S. nuclear plant. Many believe the figures should be much larger, since the local population has grown since 1982 when the calculations were made, and people beyond a 17.5 mile radius from the plant will also suffer adverse health consequences.
More recently, the Union of Concerned Scientists prepared an estimate of casualties after a core meltdown from a terrorist attack. The 2004 report entitled Chernobyl on the Hudson estimated much higher casualties than did the 1982 Sandia effort. The Union’s Dr. Edwin Lyman calculated that as many as 44,000 near term deaths from acute radiation syndrome within 50 miles and 518,000 long term deaths from cancer within 60 miles could occur, depending on weather conditions.
Indian Point is more vulnerable to a meltdown from mechanical failure than most reactors because of its age, and more vulnerable to a terrorist attack because of its proximity to New York City.
Since the terrorist attack on the World Trade Center of September 11, 2001, much attention has been paid to the possibility of Indian Point as a potential target for attack.
The reactors are also more vulnerable to a meltdown due to its parts corroding as the plant ages and as the reactors operate much more of the time in recent years; the operating factor from 2001-2004 was 95%, compared to the national rate of 90% (Table 3). Until 1994, the operating factors for Indian Point 2 and 3 were 64.7% and 50.4%, respectively.
The potential for a meltdown, while not highly likely, is a reality. A recent report by Greenpeace entitled “An American Chernobyl” identified 200 near-miss accidents at American reactors in the past two decades. Four of these were at Indian Point, all occurring since 2000 (Table 4).
III. Radioactivity from Indian Point
All nuclear reactors must routinely emit radioactivity into the environment in order to operate. There are several forms of these emissions. One is accidental releases due to leaking equipment, which can include the cladding and welds of fuel rods in the reactor core, cracks and breaks in fuel that damages cladding, corroding pipes, and cracked steam generator tubes. These scenarios result in radioactivity released into the air and water. Radioactivity is also deliberately released into local water about every 18 months when reactors refuel.
Each utility is required by federal law to measure and report radioactive environmental emissions from nuclear reactors annually. From 1970-1993, the federal government produced a comparative listing of annual emissions for each U.S. reactor (it has since been discontinued). One measure of environmental emissions is known as airborne “Iodine-131 and Effluents” or chemicals with a half life of at least eight days (and thus, are more likely to enter the body through breathing and the food chain). The list of the U.S. nuclear plants with the highest releases is given in Table 5:
The Indian Point total of 17.50 curies is the 5th highest of 72 U.S. plants. The total is greater than the 14.43 curies from the Three Mile Island plant in Pennsylvania, most of which was reported after the 1979 accident. Most of the Indian Point total occurred in 1985 and 1986, with a total of 14.03 curies from Indian Point 2. Several years later, the totals were changed to 1.90 curies; an inquiry to the U.S. Nuclear Regulatory Commission attributed the change to a “clerical error.” While the original figures are used here, using revised figures would still rank Indian Point as the 12th highest in the nation.
More recent data on emissions is now posted on the Internet by the federal government. Data for all U.S. reactors are listed from 2001-2004, by quarter, and by type of emission. Unfortunately, no information for Indian Point 2 is given, and data for Indian Point 3 is missing for various quarters.
But examination of types of airborne and liquid radioactive emissions with data reported for each quarter from 2001-2004 from Indian Point 3 is helpful in understanding the large variations over time (Tables 6 and 7). For example:
More analysis is needed to understand reason(s) for these releases. But it is clear that there are very large swings in emissions levels over time. Large increases often remain high for extended periods of time.
B. Environmental Radioactivity Levels near Indian Point
All utilities are also required by federal law to make periodic measurements of radioactivity levels in the local area near reactors, and report them to the U.S. Nuclear Regulatory Commission annually. In addition, the New York State Department of Health makes measurements in air, water, soil, fish, and vegetation, and makes results available to the public.
Some of the measurements are for levels of specific chemicals, such as Strontium-90 and Iodine-131. But others cover entire categories of radioactive chemicals (which emit alpha particles, beta particles, or gamma rays). These categories are most meaningful when trying to estimate total radiation burden to the environment.
The state Health Department maintains a water monitoring site on the Hudson River at Verplanck, which is just one mile south of the Indian Point plant. It also measures radioactivity levels in water in Albany, on the roof of the Health Department building, as a “control”, meaning the site is far from any nuclear plant. Average weekly levels of all alpha and beta emitters have traditionally been about 10 to 11 times higher in Verplanck than in Albany (Table 8). It is virtually certain that this difference is due to the operations of Indian Point, as many of these alpha- and beta-emitting chemicals can only be produced in nuclear reactors.
The Annual Radiological Environmental Operating Report for the Indian Point plant is now available on the NRC web site from 1999 to 2006. While each report lists a variety of radioactivity measurements near the plant, there are problems. There is no simple way to summarize radioactivity patterns near the plant. Measurements of some forms of radioactivity are taken infrequently (e.g. annually or quarterly). Levels of radioactivity may not always be detectable by Entergy, given the reliable detection limits of the methodologies employed. At these levels, measurement uncertainty is characteristically high, making it difficult to obtain reliable assessments.
One type of radioactivity that may be helpful in understanding local radioactivity burden is “gross beta in air”, or the total amount of radioactive chemicals that emit beta particles. Measurements are taken weekly; error margins are small; there are nine stations near Indian Point; and all measurements are detectable. Table 9 displays findings for 2006:
Perhaps the most noteworthy pattern observed
in these data is the wide variation over time. The average for the last
29 weeks of the year was 40% greater than the first 23 weeks. The average
during the late autumn (23.76 for the seven weeks November 7 to December
19) was nearly triple that of the late spring (8.07 for the eight weeks
April 25 to June 13). These patterns are consistent among the nine stations,
and cover hundreds of readings, suggesting they are due to changes in
man-made radioactivity from Indian Point.
C. Radioactivity Levels in Bodies near Indian Point
The question of how much man-made radioactivity enters human bodies was first considered in the 1950s, when the U.S. government sponsored studies that measured bone and teeth samples for Strontium-90, one of the 100-plus chemicals found in nuclear weapon explosions and nuclear reactor operations. A landmark study of baby teeth in St. Louis found that the average Sr-90 level for children born in 1964 (just as atomic bomb testing was stopped) was about 50 times greater than for children born in 1950. Furthermore, Sr-90 studies found that average concentrations in bodies plunged by about half from 1964 to 1969, after large-scale weapons testing in the atmosphere was banned. Similar studies of Sr-90 in bone and teeth in Europe found similar patterns. (Sources: Rosenthal HR. Accumulation of environmental strontium-90 in teeth of children. In: Proceedings of the Ninth Annual Hanford Biology Symposium, Richland WA, May 5-8, 1969. Washington DC: U.S. Atomic Energy Commission, 1969. Health and Safety Laboratory, U.S. Atomic Energy Commission. Strontium-90 in Human Vertebrae. In: Radiation Data and Reports, monthly volumes, 1964-1969).
Government officials dropped their in-body radiation monitoring programs in 1970, 1971, and 1982. No studies measuring in-body levels near U.S. nuclear plants existed until 1996, when the independent research group Radiation and Public Health Project initiated an effort measuring Sr-90 in baby teeth, as did the earlier project in St. Louis. RPHP used a machine designed to measure low-dose radioactivity levels and selected the REMS radiochemistry lab of Canada to establish protocols and test teeth.
The lab calculated the ratio of Sr-90 to calcium, and RPHP converted it to a ratio at birth, using the Sr-90 half life of 28.7 years. Most Sr-90 in a baby tooth is taken up during the last six months of pregnancy and the first few months of life. A tooth from a person age 28.7 years with a current ratio of 4.30 would have an at-birth ratio of 8.60. Teeth were classified according to where the mother lived during pregnancy and the first year of life, not the current residence.
RPHP has tested nearly 5,000 baby teeth, and published five medical journal articles on results. A comprehensive analysis of the study found that average Sr-90 in baby teeth were 30-50% higher in counties closest to six U.S. nuclear plants, and that average levels rose about 50% from the late 1980s to the late 1990s (reversing a prior decline), as reactors aged and were in operation more frequently. Results were statistically significant, suggesting strongly that emissions from nuclear reactors were entering bodies of local humans. (Source: Mangano JJ et al. An unexpected rise in Strontium-90 in US deciduous teeth in the 1990s. The Science of the Total Environment 2003;317:37-51).
Over 500 teeth were collected and tested from the New York metropolitan area partly supported by a $25,000 grant from the Westchester County legislature. Over half were from the four counties closest to Indian Point – Westchester, Rockland, Orange, and Putnam. The average local Sr-90 level was the highest in the area, and the highest of near six U.S. nuclear plants. Average Sr-90 decreased with distance from the plant, i.e., New York City was lower than the local area, and Long Island was lower than New York City (Table 10).
Increases in average Sr-90 in baby teeth over the past decade were also highest near Indian Point. Children born in the late 1990s in the four-county area had a 38% greater average Sr-90 level than those born in the late 1980s, while the changes in New York City and Long Island were +36% and -11%, respectively (Table 11).
While the tooth study provided some unique and important data, it is difficult to demonstrate exactly how the Sr-90 entered children’s bodies. (Some is taken from the mother’s bone stores, some is through the mother’s diet during pregnancy, and some through the baby’s diet during infancy). Sr-90 enters bodies through milk, water, vegetation, and breathing. The study limits do not, however, negate the importance of consistent and significant findings of high and rising levels of radioactivity closest to Indian Point.
The preceding data documenting high emissions
from Indian Point, high levels in the local environment, and high/rising
levels in local bodies raise questions about whether the health of local
residents have been harmed.
IV. Potential Health Risks from
Health risks from Indian Point have been virtually unstudied. The only national study of cancer rates near U.S. nuclear plants was conducted in the late 1980s by the National Cancer Institute. The study examined changes in cancer death rates before and after the startup of 62 plants, including Indian Point.
Because Indian Point 1 began operating in 1962, the NCI study compared death rates in Westchester and Rockland Counties with the U.S. rate for the periods 1950-1962 and 1963-1984. Aggregate results were published in the New England Journal of Medicine in March 1991. Table 12 provides results for the two counties.
Results of the NCI study are mixed, as rates of six types of cancer increased and six types decreased in Westchester and Rockland Counties. However, no data are examined after 1984, which makes the study outdated. In addition, the fact that only cancer deaths, not cancer cases, were examined suggests it did not comprehensively address cancer risk.
In 2003, a medical journal articles examined childhood cancer incidence (cases) near 14 nuclear power plants in the eastern U.S., covering the period 1988-1997, during which nearly 4000 cases were diagnosed. The article found that cancer rates in children age 0-9 exceeded the national rate in all 14 areas near nuclear plants. One of the 14 areas was Indian Point (Westchester and Rockland Counties), which exceeded the U.S. by 17.4%. The excess was of borderline statistical significance (p<.08, when p<.05 is considered significant). The article also examined mortality for children age 0-9 during this period. The Westchester/Rockland death rate was 1.4% above the U.S., not a significant excess.
These studies, while providing helpful
data, fall far short of addressing any potential connection between Indian
Point emissions and local risk of cancer. Much more detailed and updated
analyses are needed, especially as federal regulators examine the application
to extend the licenses of the Indian Point 2 and 3 reactors for an additional
B. Defining Local Population
While there is no uniform definition of what is meant by the “local” area around Indian Point, any study should include some or all of the four counties that flank the plant. Westchester County, the site of the site, lies to the east and southeast, while Rockland County lies to the west and southwest. These two counties were recognized by the National Cancer Institute as the “local” counties near Indian Point. In addition, Putnam County (just to the northeast) and Orange County (just to the northwest) can be considered, although area totals will largely reflect Westchester and Rockland counties, which are much more populated. Most residents of these counties live within 20 miles of Indian Point.
Several demographic characteristics that can affect health risk in counties closest to Indian Point are given in Table 14.
The current population of the four-county
area is over 1.7 million, which has nearly doubled in the past half century.
Compared to the U.S. and New York State, the local educational level is
higher, while the percentage of minorities and persons living in poverty
are lower. Thus, there are no apparent characteristics in the area suggesting
elevated disease risk. The presence of world-class medical care in New
York City is another factor suggesting local disease rates should not
exceed state and national levels.
C. Cancer Incidence
The New York State Department of Health has made cancer incidence data available on the Internet for small areas, including counties and zip codes. The most recent data covers the period 2000-2004.
Table 15 displays cancer incidence rates for the four counties, compared to the U.S. and New York State rates, diagnosed during 2000-2004, for all cancers combined.
The cancer incidence rate in each county exceeds the U.S. and state rates, for both genders (greater for females). In nearly all cases, the excess was statistically significant. If the rate for each county had been equal to the national and state rates, 3631 and 2090 fewer cancer cases, respectively, would have been diagnosed during 2000-2004.
2. Childhood Cancers
Children are especially vulnerable to the toxic properties of radiation exposure. Thus, childhood cancer is likely the most-studied disease near nuclear plants.
The New York State Cancer Registry also makes available county-specific cancer incidence data for children, defined as those diagnosed before age 20. Table 16 lists childhood cancer incidence for each of the 22 most populated counties in New York State, which accounts for 86% of the state’s population, for 2000-2004. Each county has at least 140,000 residents.
The table reveals that childhood cancer incidence in each of the four counties near Indian Point exceeds state and national rates. Rockland, Westchester, and Orange Counties have the 1st, 3rd, and 8th highest rates, respectively, of the 22 largest counties in the state (the number of cases in each of the other counties are likely to be too small to be significant). If Putnam County were large enough, it would have the 7th highest rate.
A total of 471 children in the four counties were diagnosed with cancer from 2000-2004. The rate of 20.0 cases per 100,000 children exceeds the state and nation by 12% and 22%, respectively. The excesses is of borderline significance (p<.08) compared to the state, and significantly above the U.S. (p<.003).
3. Thyroid Cancer
The specific type of cancer most strongly linked with radiation exposure is cancer of the thyroid gland. Radioactive iodine found only in atomic bomb fallout and nuclear reactor emissions seeks out the thyroid when it enters the body, and destroys and injures healthy cells.
Aside from exposure to ionizing radiation, experts have yet to conclusively identify risk factors for thyroid cancer. Thyroid cancer is the fastest-rising type of malignancy in the U.S.; the incidence rate has more than doubled since 1980, for young, middle age, and elderly adults (the disease is very rare in children). This trend, plus the sensitivity of the thyroid gland to radiation, makes it logical to examine thyroid cancer incidence near the Indian Point plant. Tables 17 and 18 show 2000-2004 thyroid cancer incidence rates for the most populated counties in New York State, for males and females.
The data show dramatically elevated rates of thyroid cancer incidence in the counties closest to Indian Point. The 4 county rate is 72% and 70% higher than the U.S. for males and females (7.4 vs. 4.3 and 21.3 vs. 12.5). While the Health Department web site does not combine rates for both genders, it appears that Rockland and Orange Counties have the highest rates of any large county in the state, followed closely by Westchester and Putnam Counties. The rate in Rockland County is approximately double that of the U.S. While thyroid cancer is not among the most common types of cancer, the total of 1202 cases diagnosed in the region from 2000-2004 makes the excess statistically significant, and worthy of further analysis.
4. Breast Cancer
Another type of cancer known to sensitive to radiation exposure is breast cancer. In 1994, a report on over 200,000 survivors of the atomic bombs used on Hiroshima and Nagasaki documented elevated rates of many types of cancer in those who received highest doses. Breast cancer in females had the highest excess (20%) of any type of cancer, except for thyroid cancer (34%). (Source: Thompson DE et al. Cancer Incidence in Atomic Bomb Survivors. Part II: Solid Tumore, 1958-1987. Radiation Effects Research Foundation, Hiroshima Japan, 1994).
The incidence of breast cancer in the Indian Point area during the most recent five years, as posted on the state Health Department web site, is given in Table 19:
Breast cancer incidence was greater than the state and nation for each county. The four-county excess was 7.0% and 5.9%, respectively. Of the total of 6502 breast cancer cases diagnosed during the period, 390 to 465 are in excess of the national and state rates, respectively. The only excesses that are statistically significant are those for Westchester and the four-county total.
In addition, the gap between the four-county and state rates of breast cancer incidence has grown in the past three decades. The excess of 1.9% in the late 1970s has increased to 7.0% in the early 2000s. The number of breast cancer cases diagnosed annually has risen from about 800 to 1300 during this time.
5. Most Common Cancers, by Zip Code.
The state Health Department has also made available cancer incidence data by each zip code in New York State, for the five year period 1999-2003. The data only cover the four most common types of cancer: (female) breast, colorectal, lung and bronchus, and (male) prostate. These account for about 55% of all newly-diagnosed cancer cases in the U.S. Actual cases are compared with the number expected if the rate in the zip code equaled the state rate for each age group.
Table 20 displays the number of cancer cases for the six zip code areas closest to Indian Point, all within about five miles of the plant, three in Rockland County and three in Westchester County (data for all zip codes in the two counties are given as Appendix 1).
There were 919 cases of the four cancer
types diagnosed in the towns closest to Indian Point from 1999-2003. Cancer
incidence in the six towns exceeded the state rate by 20.2%, while the
excess for the rest of the two counties was just 1.3%. The excess in the
six towns is highly significant at p<.0002. Local rates were significantly
higher than expected for each of the four types of cancer except for breast
D. Cancer Mortality
Data for all U.S. deaths is available for the years 1979 to 2004 on the web site of the U.S. Centers for Disease Control and Prevention. The site permits analysis by age, race, sex, and cause of death, and identifies state and county of residence. It also allows death rates for clusters of counties or states to be analyzed.
Table 21 displays the death rate for all cancers combined for the four-county area near Indian Point, compared to the state and nation, for the 26 year period in the data base.
The four-county area has virtually the same cancer death rate as the state and nation (+0.4% and +0.9%, respectively). The total excess deaths (548 and 971) are a small proportion of the total number of 84,407 cancer deaths in this period. Putnam and Orange Counties have higher rates, while Westchester and Rockland Counties have lower rates. The differences are all statistically significant, except for Rockland County.
2. Cancer vs. Non-Cancer Mortality
While the local cancer mortality rate near Indian Point is only slightly higher than the state and national rates, this pattern takes on different meaning after analyzing local death rates for other causes. Table 21 shows the local mortality rates for cancers and all other causes combined, for each age group.
For all but the elderly, the local rate of all non-cancer deaths was 21% to 26% below the U.S. standard, a large variation from the slight elevation in cancer deaths. If the local cancer mortality rate had been below the U.S. like it was for other causes, a total of 8,799 fewer cancer deaths would have occurred from 1979-2004 in the four counties.
3. Thyroid Cancer
Thyroid cancer is one of the most successfully treated types of cancer, and thus the mortality rate for this disease is very low. In the period 1979-2004, a total of 241 residents of the four local counties died of thyroid cancer. The death rate of 0.607 per 100,000 was 32.6% and 13.9% greater than the U.S. and New York State, respectively. The difference with the U.S. is statistically significant at p<.01, while the difference with New York State is not significant.
4. Correlation of Radioactivity from Indian Point with Cancer
To start examining a any correlation between radioactive emissions from Indian Point and cancer risk, RPHP compared trends in Strontium-90 in local baby teeth with trends in childhood cancer incidence age 0-9. Figure 1 includes two line graphs over a 14 year period, one each for the local trend in Putnam, Rockland, and Westchester Counties. The childhood cancer line represents periods four years after the Sr-90 line, to test the principle that childhood cancer occurs several years after exposure to the fetus. Dr. Alice Stewart first observed this phenomenon in the late 1950s when she demonstrated pelvic X-rays to the fetus resulted in nearly a doubling in the cancer death rate before the child reached age ten.
When the Sr-90 level rises, cancer incidence
in children under age ten also rises. Conversely, declines in Sr-90 are
followed by declines in cancer incidence. The correlation falls short
of statistical significance; but similar and significant findings near
the Oyster Creek and Brookhaven nuclear plants give the results credibility,
and suggest that more detailed examination is merited.
V. Studies of improved
local health after reactor shutdown
If Indian Point closes by the end of its current license in 2015, no additional radioactivity will be produced or released from the reactor core (the slow-decaying forms of radioactive waste will remain). Closing the reactor will reduce levels of these products in the environment and body.
There is a precedent for such reductions. When above ground atomic bomb tests ceased after the Partial Test Ban Treaty of 1963, chemicals that decay quickly (such as Iodine-131, with a half life of eight days) virtually disappeared. Chemicals with a slower decay rate also dropped; Strontium-90 fell 75% in milk and 50% in bones from 1964-1970, according to studies conducted by the U.S. Public Health Service. (Source: Health and Safety Laboratory, U.S. Atomic Energy Commission. Strontium-90 in Human Vertebrae. In: Radiation Data and Reports, monthly volumes, 1964-1969).
Reduced environmental radioactivity raises the question of whether disease rates would also decline, especially among the more susceptible infant and children. Again, there may be precedent for such a change. The incidence of cancer age 0-4 in Connecticut, the only state which maintained a cancer registry in the 1960s, rose as large-scale bomb testing continued; from 1959 to 1962, new cases increased steadily from 41 to 60. But after testing ended, the number of cases plunged, from 60 to 30 between 1962 and 1968 (Table 23). Cancer incidence to young children can be seen as one of the most sensitive indicators of harm from radiation exposure, as these cancers often represent insults to the highly radiosensitive fetus.
B. Precedent – Nuclear Reactor Closing
Much of the radioactivity in the core of a nuclear reactor consists of chemicals that decay relatively quickly. Thus, reactor shutdown would mean a substantial decrease in routine emissions and in emissions from a core meltdown, just days after closing. A recent report calculated that a core meltdown just 20 days after shutdown of a fully operational reactor would reduce cancer deaths within 50 miles by 50% and reduce acute fatalities by 81%. Using the methodology from the Sandia National Laboratories 1982 study, the report estimated that a meltdown at Indian Point 20 days after the reactor closed would reduce cancer deaths within 50 miles from 53,960 to 26,870 and acute fatalities within 10 miles from 867 to 166. Source: Lyman ES. The Impact of Nuclear Plant Shutdown on Severe Accident Consequences. Washington DC: Nuclear Control Institute, February 12, 2002.
Like atomic bomb test cessation, there may be a precedent for cancer reductions after nuclear reactors close and radioactive releases end. A 2002 journal article by the Radiation and Public Health Project examines reactors that closed from 1987-1998 that were at least 70 miles from any other nuclear plant. The article compared cancer incidence in children under age five in the periods prior to and after closing. For downwind areas near six closed reactors, the rate fell each time (total of -24.8%), even though there was a slight increase in the U.S. childhood cancer during this period (Table 24).
Cancer reductions for people of all ages have also occurred near closed nuclear reactors. One of the largest U.S. reactors that has closed permanently is Rancho Seco, in Sacramento County CA, which closed on June 6, 1989. The four California counties within 40 miles downwind (east) of Rancho Seco have a population of 1.9 million, roughly equal to the four counties surrounding Indian Point. This part of California also has approximately the same percentage of minorities, foreign born residents, educational levels, and poverty levels as does the U.S.
In the 1980s, while Rancho Seco was operating, the local cancer death rate was higher than the U.S. But in the 1990s and 2000s, after shutdown, levels abruptly moved below the U.S. The difference between the actual (lower) cancer death rates and an expected continuation of previous rates equals 3225 fewer local cancer deaths from 1990-2003 (Table 25).
Reductions in cancer after reactor closing
may reflect various contributing factors other than reduced radioactivity.
However, no other factors in the Rancho Seco area accounting for this
significant trend are apparent.
C. Potential Cancer Reduction After Indian Point Closing.
To the extent, if any, that elevated local rates of cancer are caused by Indian Point’s radioactive releases, closing the reactors could result in a decrease in cancer incidence and mortality. If cancer death rates in the four counties within 20 miles of Indian Point declined at a similar rate as in the four counties near the closed Rancho Seco reactor, the reduction in cancer deaths from 2016 to 2035 would be 5,203 (Table 26).
VI. Summary and Policy Implications
The preceding report covers two subjects: (potential and actual) radioactive contamination from the Indian Point reactors in the local environment, and potential health risks to local residents. Several analyses estimate that a large-scale release of radioactivity, either from mechanical failure or act of sabotage, would harm thousands, either through acute radiation poisoning or cancer.
In addition, environmental contamination from Indian Point may have already caused harm. Evidence of contamination includes reported environmental emissions from the reactors; reported levels of radioactivity in the environment; and Strontium-90 detected in local baby teeth. Official data from state and federal regulators of nuclear plants were used for emissions and environmental levels, while a novel study by the Radiation and Public Health Project was used for data on baby teeth. RPHP published five medical journal articles on the study.
The Indian Point reactors historically have emitted greater amounts of radioactivity into the environment than most U.S. plants. These emissions appear to be unpredictable, as wide variations in environmental radioactivity levels near Indian Point over time suggest. The baby tooth study, while it cannot exactly track all pathways of Sr-90 into local bodies, does document relatively high (compared to other areas) and rising levels of the isotope in counties closest to Indian Point.
Cancer data were obtained from the New York State Cancer Registry (for cancer incidence from 2000-2004) and from the U.S. Centers for Disease Control (for cancer mortality from 1979-2004). The local area near Indian Point was defined as the counties within 20 miles (Orange, Putnam, Rockland, and Westchester). The results show that:
It is important to understand that this report presents data that suggest – but not yet prove – that Indian Point emissions are causing cancer. Many factors contribute to cancer risk, and radiation exposure is just one. However, the data raise questions about a potential link, on a topic has been virtually ignored in the 45 years that Indian Point has operated. The costs to society of high cancer rates are enormous, including direct medical costs and lost productivity from otherwise healthy members of society.
Given that federal regulators are about
to review an application by Entergy Nuclear for permission to extend the
operating licenses of the two Indian Point reactors for another 20 years,
a prudent policy would be to conduct further study and not to grant any
extension until the public better understands to what extent, if any,
the threat that Indian Point presents to local public health.